Electronic Library of Scientific Literature - © Academic Electronic Press
Volume 35 / No. 1 / 2001
David S. Goldstein, Steven M. Frank
Clinical Neurocardiology Section, National Institute of Neurological
Disorders and Stroke, Bethesda, MD, U.S.A.;
Department of Anesthesiology and Critical Care Medicine, The Johns Hopkins
Medical Institutions, Baltimore, MD
E-mail: goldsteind@ninds.nih.gov
Objective. In the 1920s, Walter B. Cannon first described the
adrenomedullary response to cold, using an ingenious in vivo bioassay
based on a denervated heart preparation. Studies in humans about antecubital
venous plasma concentrations of norepinephrine, the sympathetic
neurotransmitter, and of epinephrine, the main adrenomedullary hormone, have
suggested sympathetic nervous system activation without adrenomedullary
activation. The present study used arterial levels of these catecholamines, to
determine whether adrenomedullary stimulation occurs in response to decreased
body temperature.
Methods. Eleven healthy volunteers underwent central intravenous infusion
of warm (37°C) physiological saline, followed by infusion of the same volume of
cold (4°C) saline. Brachial arterial and antecubital venous plasma
concentrations of norepinephrine and epinephrine were measured by liquid
chromatoraphy with electrochemical detection.
Results. Antecubital venous concentrations of norepinephrine increased
markedly during cold saline infusion, with smaller and statistically borderline
increases in concentrations of epinephrine. In contrast, concurrently obtained
arterial concentrations of both norepinephrine and epinephrine increased
significantly.
Conclusions. The results confirm Cannons original inference that cold
evokes adrenomedullary activation. Prior studies about antecubital venous levels
of catecholamines did not take into account the local hemodynamic effects of
cold, which would increase extraction of circulating catecholamines and
underestimate the arterial epinephrine response.
Key words: Catecholamines Hypothermia Adrenomedullary response
Man
ENDOCRINE REGULATIONS, Vol. 35, 37, 2001
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Krzysztof Kolomecki, Henryk Stepien, Magdalena Bartos, Krzysztof Kuzdak
Clinic of Endocrinological and General Surgery, Medical University of Lodz,
93-513 Poland;
Department of Experimental Endocrinology and Hormonal Diagnostics, Medical
University of Lodz
E-mail: branch@poczta.onet.pl
Objective. To estimate serum levels of vascular endothelial growth factor
(VEGF), metalloproteases MMP-2 (gelatinase A), MMP-3 (stromyelisine 1) and
metalloprotease tissue inhibitors (TIMP-2) in patients with various benign and
malignant adrenal tumours before and after surgery, as well as to evaluate if
there is a correlation between serum levels of these agents and tumour
types.
Methods. Serum levels of VEGF, MMP-2, -3 and TIMP-2 were estimated in 43
patients with adrenal tumour at the admission and, in case of surgery, again one
month after surgery. The patients were divided into 6 groups according to the
type of the tumour (I patients with adrenal cortex carcinoma, II with
benign hormonally active adrenocortical adenomas, III with benign,
hormonally inactive adenocortical adenomas (incidentaloma), IV with benign,
hormonally active phaeochromocytomas, V - with hormonally quiescent
phaeochromocytomas, VI hormonally inactive adrenal tumours of extraglandular
origin. The control group consisted of 10 healthy individuals.
Results. There was no correlation between MMP-2 serum levels and tumour
types and no significant difference between MMP-2 level before and after
surgery. There were no significant differences between TIMP-2 serum levels in
patients with adrenal tumours and the control values. Significant increase of
serum MMP-3 level was found in patients with cortex cancer and hormonally active
benign adrenocortical tumours. The MMP-3 mean serum level was also significantly
higher in patients with malignant incidentalomas than in those with benign ones.
In all groups of patients with adrenal tumours the means serum VEGF level was
significantly higher than in control patients, and it was also significantly
higher in patients with malignant incidantalomas than in those with benign ones.
After surgery the VEGF level decreased significantly in patients with
extraglandular tumours and cortex cancers who had no recurrence.
Conclusions. Since MMP-3 and VEGF serum levels were found significantly
higher in patients with malignant adrenal incidentalomas than in those with
benign ones, they might be applied as markers of malignancy of incidentalomas.
VEGF and MMP-3 levels decreased after tumour resection in all patients with
malignant tumors and increased significantly in patients with recurrence.
Therefore, they are supposed to be of prognostic value in these patients.
Key words: Adrenal tumour Vascular endothelial growth factor
Metalloproteases Angiogenesis
ENDOCRINE REGULATIONS, Vol. 35, 916, 2001
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Richard Hampl, Marta Snajderova, jan Lebl, Lidka Lisa, Marcela Dvorakova, Martin Hill, Jarmila Sulcova, Luboslav Starka
Institute of Endocrinology, 119 94 Praha, Czech Republic;
2nd Pediatric Department, 2nd Faculty of Medicine, Charles University, Praha;
Department of Pediatrics, 3rd Faculty of Medicine, Charles University, Praha
E-mail: rhampl@endo.cz
Objective. In girls with Turners syndrome a positive effect of
growth hormone (GH) therapy on statutal growth has been well documented, in
spite of the fact that the levels of GH and IGF-I in these patients are usually
within the normal range. It is known that plasma levels of sex hormone-binding
globulin (SHBG) are negatively associated with growth hormone (GH) and with
IGF-I. Limited data on SHBG levels in these patients and only scarce reports on
other than gonadal steroids in these patients are available so far. The major
aim of this study was to find out whether SHBG does respond to GH treatment.
Methods. Plasma levels of SHBG, estradiol, progesterone, testosterone and
the adrenal steroids and their precursors, namely cortisol,
17alpha-hydroxyprogesterone, androstenedione, dehydroepiandrosterone and its
sulfate were determined in 65 patients aged 2-23 years with Turners syndrome.
The patients were divided into 4 groups according to their actual treatment
(untreated, sex steroids only, GH only, GH and sex steroids) and the differences
between the groups were evaluated. With respect to dependence of SHBG and of
steroids studied on age (with exception of cortisol), their values were
expressed as per cents of medians of the physiological values.
Results. As expected, low levels of sex steroids were found. As to the
adrenal steroids, in general, their average levels were lower than in healthy
subjects but still within the physiological limits. With one exception
(androstenedione), no significant differences were found between the groups. The
levels of cortisol were undistinguishable from healthy subjects. Absolute as
well as relative SHBG levels in untreated group and in the group treated with
estrogens were normal or even lower than those reported for normal subjects of
the same chronological age. Significantly reduced absolute as well as relative
SHBG levels in comparison to all other groups were found in GH treated children.
Conclusion. The results indicate that SHBG may serve as a sensitive
biochemical marker of the response to the GH administration.
Key words: Turners syndrome Growth hormone treatment Sex
hormone binding globulin (SHBG)
ENDOCRINE REGULATIONS, Vol. 35, 1724, 2001
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Adam Gesing, Malgorzata Karbownik, Ewa Sewerynek, Joanna Jagiela, Andrzej Lewinski
Department of Thyroidology, Institute of Endocrinology, Medical University of
Lodz, 91-425 Poland
E-mail: alewin@psk2.am.lodz.pl
Objective. To examine the bromodeoxyuridine (BrdU) incorporation into DNA
of thyroid follicular cells (TFC) in the remaining thyroid lobe after
hemithyroidectomy (hemiTx) in 1, 2, 3 and 4 weeks time after surgery.
Methods. The experiment was performed on male Wistar rats. The Cell
Proliferation Kit (Amersham, UK) was used in order to detect the incorporated
BrdU. The BrdU incorporation was expressed as a BrdU labelling index
(BrdULI; a number of BrdU-immunopositive TFC per 1000 TFC).
Results. 1. No statistically significant changes of BrdULI
were observed between the particular groups of sham-operated (shamTx)-rats in 1,
2, 3 and 4 weeks time after surgery, and in comparison of each of them to the
controls (at time 0); 2. In the first 2-week period after hemiTx, an
increasing effect of that surgical procedure on BrdULI value was
observed (the highest BrdULI value was detected 2 weeks after
hemiTx); 3. In the third and fourth week after hemiTx, a decrease of BrdULI
value was observed, as compared to BrdULI groups (in 1- and 2-week
time after hemiTx), and to the controls (at time 0); 4. An increase of
weight of contralateral lobe was shown in 1, 2, 3 and 4 weeks after hemiTx in
comparison to thyroid lobe weight in intact rats.
Conclusions. During the first 2 weeks after hemiTx, the thyroid growth in
the remaining thyroid lobe seems to ensue by hyperplasia mechanisms. The thyroid
growth processes during subsequent 2 weeks (3rd and 4th) could result from other
mechanisms for example, from hypertrophy.
Key words: Bromodeoxyuridine Labelling index Hemithyroidectomy
Rat thyroid Growth processes
ENDOCRINE REGULATIONS, Vol. 35, 2530, 2001
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Y. Hirooka, J. Takagi, R. Ikai, H. Kawai, R. Nakamura, A. Nakayashiki, S. Habu, K. Otake, Y. Mori, M. Gotoh, T. Nogimori
Department of Laboratory Medicine,
Fourth Department of Internal Medicine, Aichi Medical University School of
Medicine, Nagakute, Aichi, Aichi, 480-1195, Japan,
Department of Internal Medicine, Konanshowa Hospital, Konan, Aichi, Aichi, Japan
E-mail: yhirooka@aichi-med-u.ac.jp
Objective. To develop radioimmunoassay for somatostatin receptor type 2
(SSTR2) and search for its presence in certain rat tissues.
Methods. Anti-SSTR2 antiserum has been raised in New Zealand white
rabbits immunized with a conjugate of synthetic SSTR2 with bovine serum
albumin. Radioiodination of SSTR2 was performed by chloramin T method
followed by purification of radioiodinated material on Sephadex G-25 column.
Results. The obtained antibody did not crossreact with SSTR1, SSTR3,
SSTR4, SSTR5, hypothalamic hormones, pituitary hormones, neuropeptides or gut
hormones. The assay was performed with a double antibody system. SSTR2 was
extracted from the tissues with acid acetone. The dilution curve of acid
acetone-extracts of rat hypothalamus in the radioimmunoassay system was parallel
to the standard curve. The recovery of tissue SSTR2 was about 89 % , and the
intra-assay and inter-assay variations were 4.9 % and 7.8 %, respectively. SSTR2
was found in the hypothalamus, cerebrum, cerebellum, pituitary, stomach and
testis.
Conclusions. These data suggest that this assay system is suitable for
the estimation of SSTR2 in the tissues.
Key words: Somatostatin receptor type 2 New radioimmunoassay
Peptide synthesis Tissue contents in rat
ENDOCRINE REGULATIONS, Vol. 35, 3134, 2001
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Fedor Moncek, Richard Kvetnansky, Daniela Jezova
Institute of Experimental Endocrinology, Slovak Academy of Sciences,
Bratislava
E-mail: ueenmonc@savba.sk
Objective. Histocompatible rat strains Lewis (LEW) and Fischer 344 (F344)
are often used to study hypothalamo-pituitary-adrenocortical axis function in
relation to immune system activity. It has been suggested that LEW rats have a defect
in the hypothalamic production of corticotropin-releasing hormone. The aim of
this study was to clarify differential responsiveness of LEW and F344 rat
strains to acute stress by measuring adrenocorticotropic hormone (ACTH) and
corticosterone concentrations in plasma, corticosterone in adrenal cortex and
proopiomelanocortin (POMC) gene expression in the pituitary and spleen.
Methods. Two separate experiments were performed. In the first,
indwelling catethers were used for blood sampling from conscious animals during
immobilization stress. In the second experiment, rats were immobilized for two
hours and decapitated after another 3 hrs for organ collection.
Results. Our results show that LEW strain hyporeactivity was evident from
significantly lower ACTH and corticosterone levels compared to those in F344 at
all time intervals during stress studied. Measurement of POMC gene expression in
the pituitary revealed that the difference in hormone secretion was consistent
with POMC mRNA concentrations in these strains of rats. On the other hand,
corticosterone concentrations in the adrenal cortex after stress were
significantly higher in LEW rats compared to F344. No differences in spleen POMC
mRNA concentrations between LEW and F344 rats were found.
Conclusion. The results show that differential reactivity of LEW and F344
rats is associated with different POMC gene expression in the pituitary and
probably other factors on the adrenocortical level.
Key words: Lewis Fischer Stress ACTH corticosterone
POMC mRNA pituitary adrenals
ENDOCRINE REGULATIONS, Vol. 35, 3541, 2001
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Christian A. Koch, Alexander O. Vortmeyer, Steve C. Huang, Salvatore Alesci, Zhengping Zhuang, Karel Pacak
National Institutes of Health, National Institute of Child Health and Human
Development, PREB; National Institute of Neurological Disorders and Stroke, SNB,
Bethesda, Maryland 20892, U.S.A.
E-mail: Kochc@exchange,nih.gov
We here review the literature on genetics related to pheochromocytoma. About
10 percent of these neuroendocrine tumors are hereditary and are most often
associated with multiple endocrine neoplasia type 2 (MEN 2), von Hippel-Lindau
disease, and neurofibromatosis type 1 (NF 1). Hereditary tumor syndromes such as
the aforementioned ones, are ideal to study the molecular pathogenesis of
tumorigenesis as opposed to sporadic tumors in which genetic alterations often
merely represent epigenetic tumor progression phenomena. Recent advances in
molecular genetics, especially of RET, VHL, NF1, and SDHD, helped
better understand the pathogenesis of pheochromocytoma. In this paper, we not
only summarize key points of genetic discoveries related to pheochromocytoma,
but also report in table format all known RET germline mutations related
to pheochromocytoma.
Key words: Pheochromocytoma Genetics RET VHL NF1 LOH
ENDOCRINE REGULATIONS, Vol. 35, 4352, 2001
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D. Macejovα, J. Brtko
Institute of Experimental Endocrinology, Slovak Academy of Sciences, 833 06
Bratislava, Slovakia
E-mail: ueenbrtk@savba.savba.sk
The induction of mammary gland and other organ tumours by selected chemical
carcinogens, 1-methyl-1-nitrosourea, 7,12-dimethylbenzanthracene,
diethylnitrosoamine and azoxymethane is described and their application in
experimental carcinogenesis research is discussed.
Key words: Chemically induced carcinogenesis mammary gland
1-methyl-1-nitrosourea, 7,12-dimethylbenzanthracene diethylnitrosoamine
azoxymethane
ENDOCRINE REGULATIONS, Vol. 35, 5359, 2001
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